532 research outputs found

    Cyber Inference System for Substation Anomalies Against Alter-and-Hide Attacks

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    Alarms reported to energy control centers are an indication of abnormal events caused by either weather interruptions, system errors, or possibly intentional anomalies. Although these initiating events are random, e.g., faults on transmission lines struck by lightning, the existence of electronically altered measurements may implicate the process to identify root causes of abnormal events. This paper is concerned with alter-andhide (AaH) attacks by tampering the actual measurements to normal states with the background of disruptive switching actions that hide the true values of local events from operators at the control center. A cyber inference system (CyIS) framework is proposed to synthesize all sequential, missing, or altered alarms of related substations against AaH attacks. The stochastic nature of such attack events is modeled with probabilities as an integer programming problem with multiple scenarios. The proposed method is utilized to verify alarm scenarios for a conclusion of the potential AaH attacks on the substations.postprin

    Using Clicker Technology with Rural, Low-Income Mothers: Collecting Sensitive Data Anonymously

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    As part of a multi-state study on health message development, a group of family researchers, Extension faculty, and a learning technologist used audience-response systems, or clickers, to display and record focus group participants\u27 responses to questions. This article describes how the authors used clicker technology in focus group settings, clicker training for facilitators, and lessons learned. The clicker technique is useful to collect local and personal data anonymously in group settings for program evaluation purposes. Implications for future research and Extension education are discussed

    Evaluation of Nanoclay Exfoliation Strategies for Thermoset Polyimide Nanocomposite Systems

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    Prior works show exfoliated layered silicate reinforcement improves polymer composite properties. However, achieving full clay exfoliation in high performance thermoset polyimides remains a challenge. This study explores a new method of clay exfoliation, which includes clay intercalation by lower molecular weight PMR monomer under conditions of low and high shear and sonication, clay treatments by aliphatic and aromatic surfactants, and clay dispersion in primary, higher molecular weight PMR resin. Clay spacing, thermal, and mechanical properties were evaluated and compared with the best results available in literature for PMR polyimide systems

    Comparative Analysis of the Morphology and Materials Properties of Pinniped Vibrissae

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    Vibrissae (whiskers) are important components of the mammalian tactile sensory system, and primarily function as detectors of environmental vibrotactile cues. Pinnipeds possess the largest and most highly innervated vibrissae among mammals and their vibrissae demonstrate a diversity of shapes and likely mechanical properties. These two characteristics are important for vibrotactile sensory perception. Vibrissae of most phocid seals exhibit a beaded morphology with repeated sequences of crests and troughs along their length. I comparatively characterized differences in vibrissae morphologies among phocid species with a beaded profile, phocid species with a smooth profile, and otariids with a smooth profile using traditional and geometric morphometric methods to test the hypothesis that vibrissal morphologies are species-specific manipulations of a common pattern. The traditional and geometric morphometric datasets were subsequently combined by mathematically scaling each to true rank, followed by a single eigendecomposition. Quadratic discriminant function analysis demonstrated that 79.3, 97.8 and 100% of individuals could be correctly classified to taxon based on vibrissal shape variables in the traditional, geometric and combined morphometric analyses, respectively. At least three separate morphologies were identified since phocids with beaded vibrissae, phocids with smooth vibrissae, and otariids each occupied distinct morphospace in the geometric morphometric and combined data analyses. Another important characteristic that influences the transduction of vibrotactile information to the mechanoreceptors in the follicle-sinus complex is the materials properties of the vibrissae. Vibrissae were modeled as cantilever beams and flexural stiffness (EI) was measured to test the hypotheses that the shape of beaded vibrissae reduces flexural stiffness and that vibrissae are anisotropic (orientations differ in EI). Species were significantly different and smooth vibrissae were generally stiffer than beaded vibrissae. Beaded vibrissae decrease vibrations in flow, which, combined with lower flexural stiffness values, may enhance detection of small changes in flow from swimming prey. The anterior plane of the vibrissae is likely the most biologically significant in tracking hydrodynamic trails but had lower flexural stiffness values than the dorsoventral orientation. There is likely a complex interaction between shape and mechanical properties in pinniped vibrissae but the ecological and functional implications are currently unknown

    Beta decay of 71,73Co; probing single particle states approaching doubly magic 78Ni

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    Low-energy excited states in 71,73Ni populated via the {\beta} decay of 71,73Co were investigated in an experiment performed at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU). Detailed analysis led to the construction of level schemes of 71,73Ni, which are interpreted using systematics and analyzed using shell model calculations. The 5/2- states attributed to the the f5/2 orbital and positive parity 5/2+ and 7/2+ states from the g9/2 orbital have been identified in both 71,73Ni. In 71Ni the location of a 1/2- {\beta}-decaying isomer is proposed and limits are suggested as to the location of the isomer in 73Ni. The location of positive parity cluster states are also identified in 71,73Ni. Beta-delayed neutron branching ratios obtained from this data are given for both 71,73Co.Comment: Accepted for publication in PR

    Effective media communication of disasters: Pressing problems and recommendations

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    Public health officials and journalists play a crucial role in disseminating information regarding natural disasters, terrorism and other human-initiated disasters. However, research suggests that journalists are unprepared to cover terrorism and many types of natural disasters, in part because of lack sufficient expertise in science and medicine and training. The objective of this research was to identify solutions to problems facing journalists and public health public information officer (PIOs) of communicating with the public during natural and human-initiated disasters

    Neutron Transfer Dynamics and Doorway to Fusion in Time-Dependent Hartree-Fock Theory

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    We analyze the details of mass exchange in the vicinity of the Coulomb barrier for heavy-ion collisions involving neutron-rich nuclei using the time-dependent Hartree-Fock (TDHF) theory. We discuss the time-dependence of transfer and show that the potential barriers seen by individual single-particle states can be considerably different than the effective barrier for the two interacting nuclei having a single center-of-mass. For this reason we observe a substantial transfer probability even at energies below the effective barrier.Comment: 6 pages, 9 figure
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